Angled crimp groove

ABSTRACT

An electrical connector crimp tool including a first crimp jaw section; and a second crimp jaw section pivotably connected to the first crimp jaw section. The second crimp jaw section includes a center crimp force axis directed towards an electrical connector during crimping. The second crimp jaw section includes a crimp groove for directly contacting the electrical connector during crimping. The crimp groove has a center crimp path axis which is angled relative to the center crimp force axis.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The invention relates to a crimping tool and, more particularly, to a crimping tool having an angled crimping surface.

2. Brief Description of Prior Developments

Traditional crimp tools employ crimping jaws or crimping heads which provide structural support for the crimping process. Typical examples include “C” shaped crimp heads, nest type heads, flip latch heads and scissor action jaws. This invention relates specifically to scissor jaw action crimp tools similar to the tool disclosed in U.S. Pat. No. 7,024,911 for example. Such tools may have one stationary jaw and one jaw that articulates, or two jaws that articulate. Most jaws are designed to accept crimp die sets. Other jaws are designed to operate die-less (without crimp dies). There are also jaws that have two or more grooves within each jaw with at least one of the grooves accepting a die and one groove die less (dedicated groove).

In application, most scissor action crimp tools are limited on output crimping force with upper limits at approximately 6 U.S. Short Tons. One difficulty with scissor action tools and 6 U.S. Short Tons of crimp force is the limited crimp range with traditional maximum conductor size being 500 kcmil copper. To one skilled in the art of crimping it is known that crimping 600 kcmil copper is possible with a 6 U.S. Short Ton tool with a crimping head that is “C” shaped, nested, or flip latch style. These tools employ a linear advancing die holder that is on the same longitudinal axis as the opposing die holder. As a result the crimping dies or dedicated crimp grooves are always in line with each other and the majority of the 6 tons of crimp force is applied uniformly and evenly to the connector which results in a good crimp.

With scissor acting jaws the opposing dies are often misaligned with respect to each other. As a result, the dies approach the connector in an arc fashion. As seen in FIG. 1, on large connectors B, such as 600 kcmil copper, the scissor jaw action can cause pinching of the connector B on the conductor C, thereby consuming the majority of the crimp force into the pinched area A rather than uniformly distributing the crimp force over the majority of the connector B.

There is a desire to provide a crimp tool with a scissor type of acting jaws that do not cause pinching of the connector, thereby uniformly distributing the crimp force over the majority of the connector.

SUMMARY OF THE INVENTION

In accordance with one aspect of the invention, an electrical connector crimp tool is provided including a first crimp jaw section; and a second crimp jaw section pivotably connected to the first crimp jaw section. The second crimp jaw section includes a center crimp force axis directed towards an electrical connector during crimping. The second crimp jaw section includes a crimp groove for directly contacting the electrical connector during crimping. The crimp groove has a center crimp path axis which is angled relative to the center crimp force axis.

In accordance with another aspect of the invention, an electrical connector crimp tool is provided comprising a first crimp jaw section; and a second crimp jaw section pivotably connected to the first crimp jaw section. The second crimp jaw section comprises a center crimp force axis directed towards an electrical connector during crimping. The second crimp jaw section comprises a removable crimp die having a crimp groove for directly contacting the electrical connector during crimping. The crimp groove has a center crimp path axis which is angled relative to the center crimp force axis.

In accordance with another aspect of the invention, an electrical connector crimp tool is provided comprising a first crimp jaw; and a second crimp jaw pivotably connected to the first crimp jaw. The second crimp jaw comprises a center crimp force axis directed towards an electrical connector during crimping. The second crimp jaw comprises a crimp groove for directly contacting the electrical connector during crimping. The crimp groove has a center crimp path axis which is angled relative to the center crimp force axis.

BRIEF DESCRIPTION OF THE DRAWINGS

The foregoing aspects and other features of the invention are explained in the following description, taken in connection with the accompanying drawings, wherein:

FIG. 1 is a cross sectional view of a connector crimped onto an electrical conductor;

FIG. 2 is a side view with a cut away of a battery powered hydraulic crimping tool;

FIG. 3 is side view of a conventional crimping tool working head;

FIG. 4 is a side view of a working head of a crimping tool incorporating features of the invention;

FIG. 5 is a cross sectional view of a connector crimped onto an electrical conductor with the working head shown in FIG. 4;

FIG. 6 is a side view of a working head of a crimping tool incorporating features of the invention;

FIG. 7 is a partial side view of a side view of an alternate embodiment of a working head of a crimping tool incorporating features of the invention; and

FIG. 8 is a partial side view of an alternate embodiment of a crimp die with one crimp groove offset and one crimp groove not offset.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

Referring to FIG. 2, there is a shown a battery operated hydraulic tool 10 adapted to crimp an electrical connector onto an electrical conductor. The tool 10 generally comprises a working head 12, a hydraulic drive system 14, a motor 16 and a battery 18. The hydraulic drive system 14 comprises a frame 20 with a hydraulic fluid conduit system, a ram 22 movably connected to the frame 20 and a pump 24. The pump 24 is connected to the motor 16 by a transmission 26. Movement of the ram 22 by the hydraulic drive system is adapted to pivotably move jaw sections 28 of the working head 12 in a general scissors fashion.

Although the invention is described with reference to a battery operated hydraulic tool, features of the invention could be used in a manual hand operated tool, such as described in U.S. Pat. No. 2,814,222 for example. Although the invention will be described with reference to the exemplary embodiments shown in the drawings, it should be understood that the invention can be embodied in many alternate forms of embodiments. In addition, any suitable size, shape or type of elements or materials could be used.

The jaw sections 28 are pivotably connected to each other at a connection 30. Referring also to FIG. 3, a conventional working head is shown. The jaw sections 28 each generally comprise a jaw 38 and a removable crimp die 32. However, as noted below, one or both of the jaw sections might not comprise a removable crimp die. The front ends of the jaws 38 are adapted to removably receive the crimp dies 32 (see FIG. 3) in receiving pockets 34 and on mounting pins 36. FIG. 2 shows the jaws 28 without the crimp dies attached. Each jaw section 28 has a center crimp force axis 40 directed towards an electrical connector during crimping.

Each crimp die 32 has a crimp groove 42 for directly contacting the electrical connector during crimping. The crimp groove 42 has a center crimp path axis 44 which is aligned with the center crimp force axis 40. As noted above, this type of conventional working head can result in the problem seen in FIG. 1 when used with a larger size connector. The scissor jaw action can cause pinching of the connector B on the conductor C, thereby consuming the majority of the crimp force into the pinched area A rather than uniformly distributing the crimp force over the majority of the connector B.

Referring also to FIG. 4, the invention can include a working head 50 comprising two jaw sections 52 pivotably connected to each other at the connection 30. The jaw sections 52 each comprise a jaw 54 and a removable crimp die 32. The jaws 54 each comprise a die mounting area 56 comprising a receiving pocket 58 and mounting pins 60 on opposite sides of the jaws. The center crimp force axis 40 of the jaws sections 52 are the same as the jaw sections 28. However, the receiving pocket 58 and mounting pins 60 are sized, shaped and positioned on the jaws 54 to change the center crimp path axis 62 versus the center crimp path axis 44 shown in FIG. 3. As symbolized by reference line 64 and angle 66 in FIG. 3, the center crimp path axis 62 is shifted forward 8 degrees versus the center crimp path axis 44. In an alternate embodiment the shift could be more or less than 8 degrees. Center crimp path axis 62 is no longer aligned with center crimp force axis 40. Center crimp path axis 62 is angled relative to the center crimp force axis 40 at an angle of about 8 degrees. In this embodiment the two axes 62 are aligned when the jaws sections are in their open position shown, but they could be angled relative to each other, such as angled in a rearward direction rather than a forward direction, or angled in a forward direction at less than 8 degrees difference.

The solution in this case is to rotate location of the crimp grooves within the crimp jaws (versus the location in the prior art) such that the crimp groove axes are better aligned with the connector. For a 600 kcmil copper connector using industry standard “W” crimp dies, an approximate adjustment of 8 degrees is desirable (90-82 degrees shown in FIG. 4). The rotated crimp groove compensates for the motion produced by scissor acting jaws. As a result of rotated crimp grooves, forces are more in line from die-to-die (or jaw-to-jaw for a die-less embodiment). Hence, the crimp force is more evenly distributed across the connector; producing a reliable crimp as seen in FIG. 5. The uniform crimp produces a more homogeneous crimp.

It is best to dedicate a crimp groove for one particular connector size, as in this case 600 kcmil. However it is certainly possible to have a rotated crimp groove that may do several or more sizes that deviate on sizes adjacent to 600 kcmil. It would also be possible to place a permanent groove that is rotated and can accept other dies. FIG. 6 shows an example of a die-less working head 70 with forward rotated crimp grooves 72. However, the crimp range should be limited to restrict the misalignment of crimp forces (or excessive jaw rotation) to some acceptable value. As seen in FIG. 8, it is also possible to employ one groove 80 that is not rotated and one groove 82 that is rotated on each jaw (such as on opposite sides of a center projection 84), or two rotated grooves on each jaw with one accepting die sets and the other permanent (die-less). Any variations thereof exist, with the main thrust of the invention being a rotated groove to best distribute the crimp force while using a scissor acting tool, such that the rotated groove better aligns the crimp forces on 600 kcmil copper or sizes adjacent to 600 kcmil copper. This concept is also applicable to aluminum conductor/connectors as well.

Referring to FIG. 7, an alternate embodiment is shown. In this embodiment the tool comprises the jaws 38, but the crimp die 32′ is different. The crimp groove 74 of the die 32′ is rotated forward relative to the mounting section 76 of the die 32′ (versus their relative position in the die 32). Thus, the tool does not need to be changed to practice the invention; the shape of the die might be changed instead. Alternatively, both could be partially changed.

It should be understood that the foregoing description is only illustrative of the invention. Various alternatives and modifications can be devised by those skilled in the art without departing from the invention. Accordingly, the invention is intended to embrace all such alternatives, modifications and variances which fall within the scope of the appended claims. 

1. An electrical connector crimp tool comprising: a first crimp jaw section; and a second crimp jaw section pivotably connected to the first crimp jaw section, wherein the second crimp jaw section comprises a center crimp force axis directed towards an electrical connector during crimping, wherein the second crimp jaw section comprises a crimp groove for directly contacting the electrical connector during crimping, and wherein the crimp groove has a center crimp path axis which is angled relative to the center crimp force axis.
 2. An electrical connector crimp tool as in claim 1 wherein the second crimp jaw section comprises a second crimp jaw and a second crimp die removable connected to the second crimp jaw.
 3. An electrical connector crimp tool as in claim 1 wherein the center crimp path axis which is angled relative to the center crimp force axis by an angle of about 8 degrees or less.
 4. An electrical connector crimp tool as in claim 1 wherein the center crimp path axis which is angled relative to the center crimp force axis in a rearward direction.
 5. An electrical connector crimp tool as in claim 1 wherein the first crimp jaw section comprises a center crimp force axis directed towards the electrical connector during crimping and a crimp groove for directly contacting the electrical connector during crimping, and wherein the crimp groove of the first crimp jaw section has a center crimp path axis which is not angled relative to the center crimp force axis of the first crimp jaw section.
 6. An electrical connector crimp tool as in claim 1 wherein the first crimp jaw section comprises a center crimp force axis directed towards the electrical connector during crimping and a crimp groove for directly contacting the electrical connector during crimping, and wherein the crimp groove of the first crimp jaw section has a center crimp path axis which is angled relative to the center crimp force axis of the first crimp jaw section.
 7. An electrical connector crimp tool as in claim 1 wherein the second crimp jaw section comprises a second crimp groove.
 8. An electrical connector crimp tool as in claim 7 wherein the second crimp groove has a center crimp path axis which is angled relative to the center crimp force axis.
 9. An electrical connector crimp tool as in claim 7 wherein the second crimp groove has a center crimp path axis which is not angled relative to the center crimp force axis.
 10. An electrical connector crimp tool comprising: a first crimp jaw section; and a second crimp jaw section pivotably connected to the first crimp jaw section, wherein the second crimp jaw section comprises a center crimp force axis directed towards an electrical connector during crimping, wherein the second crimp jaw section comprises a removable crimp die having a crimp groove for directly contacting the electrical connector during crimping, and wherein the crimp groove has a center crimp path axis which is angled relative to the center crimp force axis.
 11. An electrical connector crimp tool as in claim 10 wherein the center crimp path axis which is angled relative to the center crimp force axis by an angle of about 8 degrees or less.
 12. An electrical connector crimp tool as in claim 10 wherein the center crimp path axis which is angled relative to the center crimp force axis in a rearward direction.
 13. An electrical connector crimp tool as in claim 10 wherein the first crimp jaw section comprises a center crimp force axis directed towards the electrical connector during crimping and a crimp groove for directly contacting the electrical connector during crimping, and wherein the crimp groove of the first crimp jaw section has a center crimp path axis which is not angled relative to the center crimp force axis of the first crimp jaw section.
 14. An electrical connector crimp tool as in claim 10 wherein the first crimp jaw section comprises a center crimp force axis directed towards the electrical connector during crimping and a crimp groove for directly contacting the electrical connector during crimping, and wherein the crimp groove of the first crimp jaw section has a center crimp path axis which is angled relative to the center crimp force axis of the first crimp jaw section.
 15. An electrical connector crimp tool as in claim 10 wherein the second crimp jaw section comprises a second crimp groove.
 16. An electrical connector crimp tool as in claim 15 wherein the second crimp groove has a center crimp path axis which is angled relative to the center crimp force axis.
 17. An electrical connector crimp tool as in claim 15 wherein the second crimp groove has a center crimp path axis which is not angled relative to the center crimp force axis.
 18. An electrical connector crimp tool comprising: a first crimp jaw; and a second crimp jaw pivotably connected to the first crimp jaw, wherein the second crimp jaw comprises a center crimp force axis directed towards an electrical connector during crimping, wherein the second crimp jaw comprises a crimp groove for directly contacting the electrical connector during crimping, and wherein the crimp groove has a center crimp path axis which is angled relative to the center crimp force axis.
 19. An electrical connector crimp tool as in claim 18 wherein the center crimp path axis which is angled relative to the center crimp force axis by an angle of about 8 degrees or less.
 20. An electrical connector crimp tool as in claim 18 wherein the center crimp path axis which is angled relative to the center crimp force axis in a rearward direction. 